Crushing and grinding mill



l therein.

UNITED STATES PATENT OFFICE..V

JAMES F. VVINCHELL, OFISPRINGFIELD, OHIO.

CRUSHING AND GRINDING lVllLL.

SPECIFICATION forming part of Letters Patent No. 365,718, dated June 28, 1887.

Application tiled Scl temhcr 18, 182 6. Serial Na. 213,888. (No model.) y

To a/ZZ whom, it may concern:

Beit known that I, JAMES F. WINCHELL, a citizen of the United States, residing at Springfield, in the county of Clark and State ol' Ohio, have invented cert-ain new and useful Improvements in Crushing and Grinding Mills, of which the following is a specification,

reference being had therein to the accompany* ing drawings.

This invention relates to certain new and useful improvements in crushing and grinding mills, having special reference to the crushingchamber thereof, and is designed to provide for automatically allowing of the escape ot' foreign substances-such as metal, stones, &c.- in the manner more particularly hereinafter pointed out.

In the accompanying drawings, forming a part of this specification, and on which similar letters of reference indicate the saine or corresponding features- Figure 1 represents a transverse sectional View of a crushing-chamber and crusher,show ing my improvement applied thereto and a foreign substance caught between the two; Fig. 2, a like view showing the result in the position of the yielding part and the escape of the foreign substance, and Fig. 3 an in- Verted plan view of the crushing-chamber.

The letter A. designates the crushing-chain loer of a grinding-mill of the usual or any approved construction, usually constructed of cast-iron. The shaft B carries the crusher C, and also the grinding-heads. (The latter not shown.) rlhe material is fed into the chamber in any approved way.

The letter D designates a plate or portion of the chamber, the same being constructed of the saine material, preferably, as the cham` ber and adapted to fit an opening formed The plate, by preference, is of such length as to extend the entire, or as near as practicable the entire, length of the crusher or that part of the machine which does the actual crushing, and is generally 'provided with longitudinal ribs E, which serve to hold the material under operation against the action of the crusher, so as to more readily effect its reduction.

The letter F designates a yoke or other bar, which extends beneath the plate D and connects with a support at either end, as the chamber, by means of the slotted lugs G. The ends of the yoke are turned down, so as to maintain the yoke within the slots in the lugs, while at a convenient point, preferably about the middle thereof, it is provided with a screwthreaded opening and a binding-nut, H, the function of which is to engage the under side of the plate and to force and hold it in place against the chamber proper, the edges of the plate being shouldered or otherwise constructed to bind against the edges of the aperture into which it is iitted. The ends of the plate are also shouldered, the metal constitutiug the same being shown in Figs. 2 and 3, and designated by the letter I. The yoke is constructed either of cast-iron or other material, or an alloy, or of any material which is comparatively fragile, or,` if not a material of this character, then of such size as will withstand a given amount of pressure, and beyond which that will break or yield sufiiciently to give room for the passage of the substance which occasions the unusual strain. I contemplate, however, making the yoke itself of ample capacity to stand the excess of strain, and' its vpoints of support-as the lugs G-of such size a-ndv material as will withstand only the strains incident to the usual operation of the machine, but which will give to the undue pressure which is brought to bear in the chain# b er by the presence of foreign substances of the character already alluded to.

As illustrated in Fig. l, an obstructing sub stance, as a stone, is seen caught between one of the ribs E and an adjacent portion of the crusher.

lt is obvious that the crusher must instantly cease its rotation, (which is in the direction of the arrow in this example,) or that the substance must be crushed or the rib yield. As it is impossible for the crusher to immediately come to a stop, and as such substanceswill not ordinarily give, or if they do their fragments would be in the way, it results that the parts must be broken unless one or the other will yield. By my invention the portion of the chamber against which the substance is forced-as the plate D-yields, as seen in Figi2. In this illustration the yoke is seen to have broken about the middle and the plate to have consequently dropped and permitted of the passage of the obstructing element.

IOO

The plate D may be constructed'of one or more parts, and may constitute suoli portion of the chamber as is found necessary to meet the particular circumstances. I do not conne myself to any particular construction or material, the essential idea of the invention being the yielding wall.

I am aware that concaves in thrashing-machines have been constructed in parts supported by springs, and which were adapted to yield to obstructions; and I am also aware that mills have been made in which the shell was composed of a series of movable plates held in normal position by springs and adapted to yi'eld when unduly pressed upon, and I therefore disclaim such devices, the distinction between them and mine being essentially this, to wit, that my crushing-chamber is composed of a vfixed and non-yielding part having an opening therein, and of a removable part fitted to said opening and sustained by a bar or 1. The combination, with a crushing-chamber having an opening therein, of a removable plate fitted to said'openin'g, and a yoke of frangible material, by which said plate is supported against the ordinary strains and released when undue pressure is exerted.

2. The combination of the crushing-chamber having slotted lugs depending from the sides thereof, an opening in the bottom portion, a plate having shoulders extending around it and lfitted to said opening, ribs projecting inwardly from the plate, and a cast-iron yoke supported by said lugs and having a setscrew about the middle thereof, which binds against said plate and holds it in place.

3. The combination, with a crushing-chamber composed of a fixed portion having an opening therein and a removable plate having shoulders at its edges and ribs projecting into the chamber,of afragile yokesecured at its ends to the chamber and provided with a binding-screw atan intermediate point, which bears against said plate, and a Crusher mounted to operate in the chamber.

In testimony whereof I affix my signature in 5 5 

